The present invention relates to a method for removing hormones from liquids by filtration. In particular, it relates to such a method that comprises the use of activated carbon fibers for removing hormones from liquids.
Water may contain many different kinds of contaminants including, for example, harmful chemicals. In a variety of circumstances, these contaminants should be removed before the water can be used, for example before the water becomes potable. Hormones are one example of a potentially harmful contaminant that are found in drinking water. In particular, estrogens are a class of hormones and part of a group of chemicals called endocrine disrupters. Estrogens, which may come from plant-derived foods, natural excretion of mammalian females or from birth-control pills, can be discharged from sewage treatment plants, and thus be introduced into the main water supply. These estrogens have been shown to have hormone-disrupting effects on males (both human and animal). Furthermore, estrogens have been linked with declining sperm counts in the human male population and with an increased incidence of testicular, breast and prostate cancer. Research shows that sperm count in Europe fell by 3.1 million per milliliter per year from 1971 to 1990. Testicular cancer rose in England by 55% between 1979 and 1991 with 1,337 cases in 1991. Diagnosed cases of prostate cancer rose in England by 40% over the same period. See the web site for Friends of the Earth (FOE), at http://www.foe. co.uk/fund/welcome/about_foe.html. FOE is in the process of working with companies that currently discharge estrogens into their effluent streams to investigate ways of removing estrogen-type substances from those effluent streams. See Id. For a general discussion of the potential negative health effects resulting from the release of hormones into water sources, see Ridgeway, T. J. and Wiseman, H., xe2x80x9cRemoval of oestrogen and oestrogen mimics from the environmentxe2x80x9d, Biochemical Society Transaction (666th Meeting of the Biochemical Society in Sheffield, England), Vol. 24(4), p 675-680 (November 1998).
To date, a filter capable of effectively removing hormones and in particular estrogens from water is not available. Applicants have surprisingly discovered that a filter comprising activated carbon fibers completely removes hormones from water.
Accordingly, an object of the present invention is to provide a method for effectively removing hormones from a liquid source, wherein the method involves the use of a filter comprising activated carbon fibers. The effective removal of hormones using such a filter has not previously been demonstrated by the prior art. The filter used will preferably present a low resistance to the flow of liquid through the apparatus, and will remove the hormone from a substantial volume of liquid before becoming saturated.
The present invention relates to a method of removing hormones from a liquid, the method comprising contacting the liquid with a filter including activated carbon fibers. The invention also relates to an article of manufacture comprising (i) a filter including activated carbon fibers and (ii) instructions informing a user that the filter is capable of removing hormones from liquid.